"This is EDTA. It's an anticoagulant. We use it to treat blood clots. Look what happens when I introduce it onto a sample of vampire blood. The reaction's energetic. "
EDTA (full name Ethylenediaminetetraacetic Acid) is an anticoagulant. It was discovered by Karen Jenson that the acid explodes on contact with vampire blood and it is manufactured into a weapon to be used by Blade during his raid on Deacon Frost's hideout. During the final confrontation with Frost, Blade injects him with several doses of the EDTA after he gains the powers of La Magra, causing Frost to swell up enormously and explode.
Scud later designs a weapon to be worn on the wrists that will pump the target full of EDTA via punches. Blade attempts to use this during his first confrontation with Jared Nomak, only to find out that the EDTA has no effect on Reapers.